The Inside Run – 2017 vol. 4

Front Runner Sports are pleased to present a practical, monthly summary of recent research relevant to distance runners. Our expert team will pick their highlights from the previous month to give YOU The Inside Run on how new and practical research can assist you to beat YOUR best. Please see our summary below!

Is there an Economical Running Technique?

This article came out in 2016 but we came across it again recently and thought it was worth sharing. Running technique is individual and highly variable even amongst elite athletes. However, when looking specifically into running economy (how much aerobic energy does it take to run a particular pace) there are a few common themes that the research supports. This article by Moore et al. reviews the available literature on modifiable biomechanical factors that affect running economy. Now one key thing to understand is that an increase in running economy doesn’t necessarily lead to an increase in running performance, it simply means you will use less energy (O2) for a given pace. So whilst it is highly correlated, a more significant relationship between economy and performance will exist the longer your goal event is (i.e. expect greater correlation on the road for 21-42km vs. the track for 5-10km).

Numerous factors were identified as being able to positively influence running economy (check in with the article for the full list), however for simplicity, we would like to highlight some of the easier changes that runners can implement. As previous readers of TIR would know, reducing preferred stride length by up to 3% (resulting in a faster cadence for the same pace) will not only reduce joint loads but will increase running economy. This is due to the foot landing closer to the body’s COM and therefore reduces ground contact time and vertical oscillation. GPS watches, foot pods and video analysis are all effective ways of monitoring variables such as stride length and rates to optimize your running economy.

Another factor worth addressing here is your running footwear. A compliant shoe (i.e. one that feels comfortable when running) and lightweight shoes also improved running economy. However, as we have discussed before on TIR, lighter is only better if the shoes are still comfortable and possess the necessary cushioning to match your goal pace & distance (i.e. a shoe that is economical for a 5km road race will not be economical for a 42km Marathon and vice-versa). Find a shoe that is the most comfortable at the speed you’re planning to run in that shoe and ensure it has sufficient cushioning for your individual needs for your goal event.

Following on from our brief look into footwear comfort, this article by Panagiotis et al. looks into subject specific stiffness of therapeutic shoes and orthoses. Whilst they did not look into runners specifically, the principle of self-selected footwear stiffness still applies. Varying levels of stiffness in a shoes cushioning were tested for their capacity to reduce plantar pressure. As we have spoken about previously, what was optimal was highly individual, however one common theme was BMI (body mass index). Subjects who had a higher BMI found stiffer cushioning materials reduced plantar pressures.

If we link this back to running shoes, runners of different builds and different goals will find different shoes more or less comfortable, as influenced by the pressure they feel beneath their feet. Different brands use different types and magnitudes of cushioning materials that will all feel different. When visiting your local running specialty store, make sure you try on different brands and models to ensure you get the right level of stiffness and therefore comfort in your shoes.

We’ve said it before and we will say it again – reducing ground contact time (GCT) is crucial to fast and efficient running. Having your feet get on and off the ground quicker will lead to a greater proportion of your propulsive force being produced from the elastic fibres that make up the Achilles & arch (this saves muscular work, enhancing economy) as well as a stiffer lower limb and reduced vertical oscillation (allowing you to move over the ground and through the air quicker). But as runners, how we can we train our body to reduce GCT?

This paper reviewed the effect of augmented (external) feedback on GCT in well-trained runners. The key message from this paper, was that regardless of what intervention you may use to reduce GCT (drills, ladders, wicket runs, metronome etc.) the runner will only improve if they receive outcome based feedback on whether their GCT actually reduced or not. The kicker from this study is that even though the control group (who received no external feedback) in this study received the same instructions and participated in the same training sessions as the intervention group (who were made aware of their GCT), they didn’t improve GCT. So even if you are doing an exercise prescription to help reduce GCT, ensure you are made aware of the external outcome to begin to create the motor control necessary for significant and sustainable change.

The primary benefit of having a coach oversee your training sessions and write your training programs is the elimination of what is known as Athlete Bias. As they are doing the training themselves, athletes can often get emotionally attached to their training and lose the objectivity behind what they are trying to achieve. A common example may be doing an extra rep in training due to the satisfaction of feeling as though you’ve done more work, which must be good. However, if doing that extra rep results in an accumulation of fatigue that effects the following days training or means you lose the desired physiological benefits the session was aiming to work on, then the positives (largely mental) are often outweighed by the negatives (largely physical). Sometimes doing less (or more) is better and having someone external to you (i.e. a coach) is the best person to look after the specific details of a training session or program.

This study looked at repeat sprint performance in youth footballers and compared a set recovery period with a self-selected recovery. As would be expected from goal driven athletes, the self-selected recovery times were shorter than the standardized recovery period. This resulted in premature blood lactate accumulation and reduced performance. Whilst this is a very specific population and sessional structure, the principle can be applied to all athletes. Having a coach prescribe recommend recovery times based on the session aims will typically lead to better execution of the session and therefore enhanced training adaptation towards the athlete’s goals.

This last article jumped out at us for a few reasons, but mainly to highlight how adaptable to the body can be! This case study highlights the story of a runner who had his Tibialis Anterior muscle (the muscle runs alongside the shin to pull your foot up) diagnosed as absent on the left side whilst he was training for his debut Marathon (at age 46y). Not to let this deter him, he went on to complete 20 Marathons with a PB of 3h 16min. As we referred to in article one, each runner will display his or her won individual biomechanics and even though a major dorsi-flexor on one side was not present, the body can adjust with different muscle patterns to compensate for the power and stability loss and once the body adapts to new loading patterns, can perform at a high level. The take home message, with running there are minimal excuses!